I have a question regarding data flow in the following environment:
3 sites, each a seperate NBU domain with a 5230 appliance and multiple windows servers (2K8R2 & 2K12R2)
I use AIR to replicate backups between the sites
1 scenario is as follows:
Step 1 Exchange DAG backed up to 5230 in site A
Step 2 Backup replicated to 5230 in site B
Step 3 Replicated copy imported into 5230 in site B
Each of the above steps runs successfully and the backup is available for restore in site A and site B as expected.
Here is the question:
Whilst step 3 (Import) is taking place on the 5230 in site B I am seeing a lot of network traffic between the 5230 in site B and the exchange server (where the backup originated) in site A !! Surely there should be NO communication between the appliance in site B and 'anything' in order to perform an import of a replicated backup image ? If anything traffic between the appliances, but not back to the originating client ?
What am I missing here ?
Yes I am.
But - why does this need to go back to the original backup host ? The backup has been taken to the 5230 in site A and the GRT cataloging completed. We are then performing optimized replication from the 5230 in site A to the 5230 in site B which includes the catalog information. Also, I understood that the GRT processing used a stream handler to 'inspect' the backup stream and produce the required catalog information as the backup was being processed ??
Another point here is that I am sseeing the same type of communication from the remote appliance back to the original host when replicating an image from an SQL server backup - no GRT in play here.........
What i gather from colleagues is that GRT duplication (and probably replication) would require some one to mount the image. And apparently, unless a proxy is configured that job goes to the client. I've asked some people at Symantec too, will see if I get a reply.
No explanation of what is happening with SQL.....
OK - interesting.......
Still puzzled why it needs to mount the image again - all the GRT processing hhas already been done during the initial bakup and required data should be already available in the backup stream / catalog information held on th first appliance.
From someone on tech support
"When you perform a GRT backup, the client (bpbkar via bpcd) will be sending the GRT catalog information to bpdbm on the Master. It does this after the snapshot has finished and after it has backed up the snapshot.
When you duplicate the GRT backup image it will always connect to the client to create a new catalog for the new image unless you have disabled this on the Master server in Host properties."
I am guessing this will happen with AIR as well. I'll have more information next week.
interesting.. first time I am hearing that AIR import job is reaching out to client. But what for ?
And even for the SQL, I do not see a reason why the import job has to communicate with client again. It has all the information in the SITE A only.
I am glued
Yes the more i look into this the more its gets confusing. I've got another client where the GRT images gets imported fine, but when the duplication to tape happens in other domain it tries to connect back to the client in the original domain.
I was told to use a backup proxy in the original domain, but this doesn't make sense to me. Firstly, if the details about the backup proxy is kept in the properties of the source client, then how is the other domain master/media supposed to access it? Unless you put the secondary master into that client's properties too.
SymAJ, you wanna try this. I don't have a domain to play.....